Known float type chlorinators include float means having a central aperture through which a tubular container is inserted and secured at a desired level so that pellets of chlorinating material within the container are dissolved due to contact with pool water to effect dissolution of the pellets and chlorination of the water. Normally the level at which the pellet containing container is mounted relative to the float is such that some of the material contained within the float is disposed above the level of the surface of the water so that as the chlorinating process proceeds, unused material above the surface of the water is lowered into the lower portions of the container and into contact with the water. This type of container is designed to prevent simultaneous contact of the entire chlorinating material in the floating container with the body of water because such contact would effect a concentrated chlorinating action initially which would diminish in concentration and effectiveness as the material dissolves. Such devices however are not responsive to the size of the pellets and are represented by U.S. Pat. No. 3,598,536 Christensen issued Aug. 10, 1971.